SCHINDLER Ivo VŠB - Technická univerzita

Spoluautoři SCHINDLER Ivo, RUSZ Stanislav, HANUS Pavel, KOPEČEK Jaromír

Iron aluminides with 40 at.% of aluminium are promising structural materials that are suitable for high-temperature applications. Their more extensive industrial use is so far hindered particularly by their susceptibility to formation of surface cracks at forming in as-cast state. This may be prevented with high efficiency by use of protective capsules or by heating of forming tools. Thanks to the latter method it was possible to form successfully the samples from aluminide of the type Fe-40at.%Al-Zr-B by uniaxial compression with use of anvils that were locally heated on the plastometer Gleeble 3800 by the system of resistance heating. The initial material was obtained in the form of laboratory castings with highly heterogeneous structure, which would prevent an objective evaluation of the course of structure-forming processes by metallographic methods. That's why it was necessary to slightly roll the castings in protective capsules and anneal them at the temperature of 1200 °C for the time, that would ensure full recrystallization and homogenization of the formed structure. The samples with homogenized structure were at the temperatures from 900 to 1100 °C subjected to deformation 0.2 and to isothermal annealing lasting from 0 to 240 s. Microstructure fixed by water cooling was then subjected to structural analyses, which led to obtaining of unique information on kinetics of static recrystallization of the investigated alloy in dependence on the parameters of isothermal annealing.